The backward motion phenomenon is widespread in inertial impact, stick-slip, and parasitic piezoelectric actuators, and seriously limits the development of these actuators for micro-manipulation applications. To solve this problem, a piezoelectric inertial rotary actuator based on a special wiring scheme is proposed. By changing the pair of piezoelectric vibrators in the traditional actuator to have opposite connection modes, the proposed actuator implements a two-step operating mode over one cycle and suffers no backward motion. Thus, the proposed actuator essentially eliminates the backward motion phenomenon under all conditions. Compared with other methods for controlling backward motion, which typically require additional friction-control or complex signal-control systems, the proposed wiring method has the advantages of simplicity of structure, ease of control, and high stability.

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Aiming at the performance requirements of positioning accuracy and stability of piezoelectric inertial actuators in fields including micro‐operation and biomedical engineering, a piezoelectric inertial actuator with wedge‐shaped friction foot structure using bimorph films is proposed in this paper. The wedge‐shaped friction foot structure can adjust the friction force in different driving stages, which suppresses the backward motion and effectively improves the output performance of the actuator. And the bimorph films are processed by Micro Electromechanical Systems (MEMS) manufacturing process technology. It enables the actuator to move steadily with a small tip mass and facilitates the miniaturization of actuator. The simulation model is constructed based on the dynamic model of actuator and the prototype parameters are optimized from the results of simulation tests. Then a series of output performance experiments are carried out. Experimental results show that the proposed actuator has the advantages of high resolution, stability, and displacement linearity. And the highest resolution of 0.035 µm is achieved. Depending on above results, the cell drug injection simulation experiments are successfully conducted. The success of experiments shows that the prototype has good output performance and great application potential and value in the field of cell manipulation.